Canadian Patent Application 2,431,604, describes a method of circulating fluids through a reciprocating downhole tubing pump. In accordance with the teachings of that method, the following steps are taken. A first step involves providing first means for mechanically displacing and disabling, without removing, a ball from a ball seat on the travelling ball valve. A second step involves providing second means for mechanically displacing and disabling, without removing, a ball from a ball seat on the standing valve assembly. A third step involves activating the first means to prevent the ball from engaging the ball seat on the travelling ball valve and the second means to prevent the ball from engaging the ball seat on the standing ball valve assembly and circulating fluids through both the travelling ball valve and the standing ball valve assembly.
The circulation of fluids through the downhole tubing pump is usually sufficient to remove any sand build up which is causing a blockage and restore circulation. Unfortunately, there are blockages that are so severe that circulation cannot be restored using this method.